let str = "129171111222222333333337777777777";
//统计出现次数
function getMax(str) {
    let result = {
        count: 0,
        key: null
    }
    for (let i = 0; i < 10; i++) {
        let arr = str.split(i);
        if (result.count < arr.length - 1) {
            result = {
                count: arr.length - 1,
                key: i
            }
        }
    }
    console.log(result);
    return result;
}

//字符串从小到大培训
function sort(str) {
    let arr = str.split("");
    arr.sort((a, b) => {
        return a - b
    })
    return arr.join("");
}
console.log(sort(str));

console.log(Math.tanh(1))
console.log(Math.PI/4);


